Protective door structure

ABSTRACT

The protective door structure for filing cases, safes, vaults, and the like to protect against illegal, forced or surreptitious entry has a central body portion composed of a metal plate with a metal ring secured thereto with a casehardened steel plate located within the ring. A matrix of urethane plastic material completely encases the central body portion of the door and forms the external door shape. The plastic portions exposed to attack have a tight pattern of hardened steel balls or shot embedded in the matrix. The entire assembly is formed with properly spaced openings for housing the lock mechanism.

I United States Patent us] 3,638,589

Shoop Feb. 1, 1972 [54] PROTECTIVE DOOR STRUCTURE 2,750,902 6/l956McClellan ..l09/8l 3,380,406 4/1968 Gosnell ..l09/80 [72] James shmpCanmn Ohm 3,431,8l8 3/1969 King nan/404 [73] Assignee: Diebold,Incorporated, Canton, Ohio Primary Examiner-Reinaldo P. Machado [22]Flled' 1970 Attorney-Frease & Bishop [21] Appl. No.: 7,506

[57] ABSTRACT The protective door structure for cascs afes vault Ill.and the to protect against illegal forced or surreptitious [58] Field ofSearch ..l09/64, 76, 77, 80, 82, 83, entry has a central body pol-ioncomposed f a n plate 109/84 with a metal ring secured thereto with acasehardened steel plate located within the ring. A matrix of urethaneplastic [56] Reierences Cned material completely encases the centralbody portion of the UNITED STATES PATENTS door and forms the externaldoor shape. The plastic portions exposed to attack have a tight patternof hardened steel balls 881,032 3/1908 Schultz "109/83 h t b dd d in thematrix, The entire assembly is formed 952,877 3/1910 Cowper 81 withproperly spaced openings for housing the lock 997,785 7/1911 Fish....lO9/77 mechanism 1,463,498 7/1923 Burgess ..l6l/404 1,561,845 11/1925 Goldsmith 109/76 14 Claims, 11 Drawing Figures 4 IS IS i8 I be |oI PATENIEBFEB m1? 3,638,589

sum 1 w a ATTORNEYS w 8 AS 5 w. 7 m s 6. W a J PATENTED FEB 1 1872ATTORNEYS PATENTEU KB I M SHEET 3 OF 3 INVENTOR. Jar/ms D Show ATTORNEYSPROTECTIVE DOOR STRUCTURE CROSS-REFERENCE TO RELATED PATENTS Thedrill-resistant structures shown in copending applications Ser, No.785,275 filed Dec. 19, 1968 and Ser. No. 874,518, filed Nov. 6, 1969 andboth now abandoned, of Newton J. Krug and James D. Shoop may be used inthe construction of the improved doors.

BACKGROUND OF THE INVENTION 1. Field of the Invention The inventionrelates to protective door structures incorporated in safes, chests,filing cases and like security products. Such door structure is locatedat different positions in a security product to provide easy access byauthorized personnel and the combination lock for the door isincorporated therein. A security product may be one used for filing orstorage of money, valuables or classified documents by government,industry, stores, places of business and individuals to resist or delayattack by an intruder and thus delay or defeat attempts at illegal,forced or surreptitious entry to the interior of locked protectivesecurity products.

2. Description ofthe Prior Art Prior protective door structures havebeen made of various metal components and arrangements, such as forgingsof malleable steel welded together with a casehardened steel platesandwiched therebetween, for example, and used as doors for safes, etc.,to protect or shield from illegal attack the zone in which the lockingmechanism is located. These prior armor plate arrangements have veryfavorable protective properties from the standpoint of drill resistancebut are very expensive to manufacture and thus present an unfavorablecost factor. Likewise, the prior protective door structures requireconsiderable machining, welding, boring, grinding and painting toproduce the finished product due to the outer surface being of metal,thus increasing the cost and time of manufacture.

SUMMARY OF THE INVENTION Objectives of the invention include providing anew protective door structure having extremely high drill resistanceefficiency which may be used to house the appropriate combination lockmeans and protect vital areas in security products so as to prevent ordelay illegal, forced or surreptitious entry to the lock or to theinterior of the security products protected by the door structure;providing a new protective door structure cheaper for comparableprotection than the most efficient known prior art arrangement;providing a new protective door structure which is extremely simple tomanufacture by eliminating machining, welding, drilling, filing andpainting; providing a new protective door structure which resists beingpunched through as well as being drilled through; and providing a newdrill-resistant door structure which achieves the stated objectives,simply, effectively and economically and solves problems and satisfiesexisting needs.

These objectives and advantages are obtained by a protective doorstructure, the general nature of which may be stated as including ametal front plate, metal ring means secured to the front plate formingdoor sidewalls, a casehardened steel protective plate attached to thefront plate within the ring means; a matrix of plastic material,preferably urethane, en casing the plate and ring means and forming theexternal door shape; and a series of hardened balls or shot, preferablymetal, arranged in a tight pattern in one or more layers with adjacentballs in contact with one another embedded in the urethane matrix overthe outer surfaces of the front plate and ring means sidewalls.

BRIEF DESCRIPTION OF THE DRAWINGS Preferred embodiments of theinvention-illustrative of the best modes in which applicant hascontemplated applying the principles-are set forth in the followingdescription and shown in the drawings and which are particularly anddistinctly pointed out and set forth in the appended claims.

FIG. 1 is a perspective view of a protective door structure with ahandle and locking mechanism attached;

FIG. 2 is a front elevational view of the protective door structureshown in FIG. 1, with parts broken away and in section;

FIG. 3 is a vertical section on line 3-3 of FIG. 2;

FIG. 4 is a fragmentary section on line 4-4 of FIG. 2;

FIG. 5 is a rear elevational view of the parts shown in FIG.

FIG. 6 is a fragmentary section on line 6-6 of FIG. 3;

FIG. 7 is a rear elevational view of an alternate construction of aprotective door structure;

FIG. 8 is a vertical section on line 8-8, FIG. 7;

FIG. 9 is a side elevational view of the plate and support assembly ofthe alternate construction of FIGS. 7 and 8;

FIG. 10 is a perspective view of one of the support member components;and

FIG. 11 is a sectional view of another arrangement similar to FIG. 8.

Similar numerals refer to similar parts throughout the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT A typical embodiment of improvedprotective door structure is indicated generally at 1 in FIG. 1 andincludes a door handle 2 and combination lock 3.

The door 1 (FIGS. 1 through 6) has a circular metal front plate 4 whichmay be formed of low-carbon steel or casehardened steel, depending uponthe degree of protection desired. Plate 4 provides the main bodyreinforcement of the door structure. A metal ring 5, concentricallylocated, preferably is tack-welded at 6 to plate 4, and a rectangularsecurity plate 7 of tool steel or the like having a high coefficient ofdrill resistance also is tack-welded at 8 to plate 4.

Front plate 4 is formed with a central opening 9 and an aligned opening10 is formed in the center of security plate 7. The dial spindle, notshown, of the combination lock 3 may extend through openings 9 and 10.Ring 5 is formed with three openings 12 equally spaced along itscircumference through which lock bolts of typical locking mechanism (notshown) may project.

Prior to welding security plate 7 to front plate 4, a hardened steelball 13 is placed in recess II to provide extra protection for acritical area of the combination lock.

One of the usual methods of attack used by an intruder or safecracker isto drill through the door of the safe to the housing of the combinationlock so as to gain access to the means for holding the lock boltinoperative in locked position and to release and move such lock bolt.Sometimes this method of attack involves drilling and sometimes itinvolves drilling followed by punching. Front plate 4 and rectangularsecurity plate 7 provide the usual and standard armor protection againstsuch attack.

Plates 4 and 7 and ring 5, assembled as described, are embedded within amatrix 19, formed of plastic material, preferably cast urethane plasticmaterial, to form the completed door shape or structure, as shown. Thematrix portion generally indicated at 14 located over the front exposedsurface 15 of front plate 4 provides additional protective means for thedoor. The matrix portion 16 surrounding the exposed surface 17 of ring 5provides additional protection for the ring portion of the door 1.

A series of spherical steel balls 18 are cast within and embedded withinthe portions 14 and 16 of the plastic urethane matrix 19 as the latteris cast. At the same time, the steel ball 13 located in opening 11 inplate 4 is also embedded in the cast matrix 19.

All steel balls 18 in any matrix portion 14 or 16 preferably have thesame diameter. However, the size, hardness, and grade of steel of thesteel balls 18 may be varied depending upon the degree of protectiondesired.

For example, steel balls 18 may be made of carbon steel or stainlesssteel having at least a hardness of from 50 to 54 Rockwell C-Scalehardness. Balls 18 need not necessarily be steel or metal balls, but maybe formed of ceramic material, such as Diamonite, an extremely hard andtough ceramic material known in the trade.

The balls 18 do not necessarily need to be truly spherical balls but maybe commercial hardened steel shot," such as 5/l6-inch shot, which iscommercially available and used, for example, in tumbling procedures.Such shot is generally round, but it may have some out-of-roundness and,therefore, cannot be said to be truly spherical.

Balls or shot 18 are arranged in a tight pattern, (FIGS. 2, 3, 4, and 6)with each ball preferably in contact with the adjacent ball. The numberof rows of balls 18 and the corresponding thickness of the protectiveareas 14 and 16 can vary and is determined by the degree of protectiondesired and cost factors.

Where it is attempted to drill through protective portion 14 or sidewallportion 16, as soon as some penetration of the urethane matrix 19occurs, the point angle of the drill engages one or more of the balls 18and the drill may be deflected thereby to such a degree that the drillbreaks. In the absence of breakage, even though the drill is deflected,the point angle of the drill engages and attempts to bite into thespherical hardened surface of one or more of the balls 18. This resultsin the balls spinning within the urethane matrix because of the naturallubricating characteristics of the material. Balls 18 in spinningfreely, driven by the rotating drill thus offer great resistance to theability actually to drill completely through areas 14 or 16.

The direct contact between adjacent balls 18, one with another, withinurethane matrix 19 prevents the balls engaged by the drill from beingmoved laterally of the drill axis.

Although plastic materials having lubricating properties, such asurethane, have been indicated as preferred, there are some plasticmaterials that have very little lubricating characteristics. These whenused provide some adhesion between the balls and matrix which results inthe balls being difficult to spin or turn. Under such circumstances, thedrill will break as it attempts to bit into the ball surface.

Some adhesion between the ball and its socket in the matrix is desirableso as to inhibit removal of a ball when a core drill is used in anattempt to drill a hole having the same diameter as a ball. Under theseconditions, the core drill cannot reach the plane of the centers of theballs because of interference by the balls surrounding and contactingthe particular ball being core drilled. The result is that the plasticmatrix material holds the ball against later removal for example by amagnet after removal of the core drill. It goes without saying that thehardened rounded surface of a ball partially exposed by a core drilloffers no means for gripping the ball other than perhaps by a magnet forremoval.

Areas 14 and 16 are likewise impervious to attack by punching. If one ofthese areas is partially penetrated by a drill, the drill withdrawn, andan attempt is made to insert a punch in the partially drilled hole topunch through area 14 or 16, or to punch one or more balls 18 throughthe urethane matrix 19, or to spread the matrix and balls apart by thepunching action; front plate 4 or metal ring 5 prevents the punch fromfurther penetration. Also the door frame of the safe or chest (notshown) with which the protective door is engaged prevents spreading ofthe balls 18 and matrix 19.

Protective area 14 is formed with a central opening a through which thelock spindle extends, and area 16 is also provided with three openings12a to coincide with openings 12 in metal ring 5.

Matrix l9 completely encases the back portion of the assembly of plate 4and ring 5 as well as the back surface 21 of security plate 7. Thus, theexposed rear surface 22 of front plate 4 within ring 5 is covered by athick wall 23 of urethane. An opening 24 is formed in the center of wall23 which coincides with openings 10, 9, and 10a of plate 7, front plate4 and protective area 14, respectively. Opening 24 may be enlarged at 25within a collar portion 25a of matrix wall 23 to cooperate withdoor-locking mechanism parts, not shown.

A circular opening 26 also is formed in wall 23 for receiving relockmechanism. Opening 26 is directiy in line with recess 11 formed in frontplate 4 which houses protective steel ball 13. Several posts 27,provided with openings 28, may be formed on wall 23 for mountingportions of the locking mechanism.

A portion of protective area 14 extends outward forming a large hingeportion indicated generally at 29 provided with an opening 30 receivinghinge pin 31. Pin 31 is pivotally connected to the safe for opening orclosing the door.

Protective door structure 1 may be made by placing the completedassembly of the front plate 4, metal ring 5 and security plate 7 in adie or mold cavity, with balls 18 arranged in the die or mold cavity atthe exposed areas most subject to attach where additional protection isdesired. Urethane or other plastic material is injection molded in thecavity, completely encasing the metal assembly in a urethane jacket orcase with the exposed areas protected by the steel balls 18.

SECOND EMBODIMENT A modified protective door structure 20 is shown inFIGS. 7-9 having spaced parallel metal reinforcing plates and hardenedsteel shot embedded in a urethane matrix or case.

Two circular mild steel plates 32 and 33 are used in the door 20 asinternal reinforcement and plates 32 and 33 are assembled as a cagelikestructure (FIG. 9) by welding Z-shaped spacers 34 at 35 to the plates 32and 33.

Plate 32 is formed with a central opening 36 through which a dial shaftor spindle of a combination lock may extend. Plate 33 has a largercentral opening 37. The space 38 between rear face 39 of plate 32 andinner face 40 of plate 33 is filled with steel shot 18 embedded inurethane matrix 41.

A central opening 42 is formed in matrix 41 concentrically located withrespect to openings 36 and 37. Matrix 4] also has a large central recess43 formed therein to receive door lock mechanism.

Members 34 each have a web 44 provided with an opening 45, a flange 46extending from one edge and spaced flanges 47 extending from the otheredge.

Passages 49 are formed in matrix 41 extending from the outer edge 50 ofmatrix 41 to recess 43 and are aligned with spacer openings 45, toreceive locking mechanism bolts. A thin coating 51 of the urethane ismolded over the outer surface 52 of plate 32 when the urethane matrix 41is molded.

THIRD EMBODIMENT Another modified door structure is shown at 53 in FIG.11. Door 53 is similar to door 20 except that the front plate 320 isthinner and the urethane matrix jacket 54 bonded to the front 55 ofplate 32a is very thick and contains a number of layers of embedded shot18 to provide maximum drill-resistance protection.

The matrix 54 is formed with an opening 56 to accommodate a lockspindle. The lock dial may be located in recess 57.

Thus, the entire locking mechanism for the door 53 is protected fromattack by the shot embedded urethane matrix portions 54 and 41. Thethickness of matrix portions 54 and 41 and of plate 32a may be varied tosecure the desired degree of protection.

The front door surface 58 and side door surfaces 59 may be shaped to anydesired contour during molding and thus present smooth, hard, attractivesurfaces without the problems and expense encountered with prior exposedmetal door surfaces.

The doors shown in the drawings are typical circular doors for smallsafes or money chests. Their sizes may be varied for larger safes andthe shape may be rectangular rather than circular if desired.

Also the door structures may have any desired shape, the shape beingdetermined by the outer shell or coating of molded urethane formed bythe mold in which the reinforced urethane door is molded. Heretofore,doors for safes and the like made of metal required extensive andexpensive machining, grinding, and polishing operations to obtain thedesired final finished shape and appearance. Such operations and theirexpense are eliminated by molding the main door body of urethane.

Furthermore, the reinforced urethane door is not subject to rusting, andthe urethane surfaces resist scratching, marring or clinging whichnormally can injure the outer metal surfaces of a metal safe door.

Any desired color may be incorporated in the urethane as molded, tocolor the urethane casing or coating throughout. Thus, painting,sometimes used for metal safe doors, is eliminated.

The rate that the molded urethane door burns when attacked with a torchis substantially the same as the rate that metal forgings are burned insimilar doors formed from forged components. Thus, the improved doorstructure has approximately the same torch burning resistance as priordoors. However, the improved door has an added advantage in respect totorch burning resistance in that when burned, the urethane gives offfumes and has a napalm effect which provide very dangerous conditions inattempting to burn through a urethane door with a torch.

Although security plate 7 provides additional protection for door 1 ofFIG. 3, other door protective means may be incorporated in any of thedoors shown by including such known protective devices as copper plates,or combined torch and tool-resistant plates, any ofwhich may belaminated within the urethane case.

Balls or shot 18 embedded in the protective areas of the improved doors,in addition to increasing drill resistance, also reduce the cost of thedoor since shot is considerably cheaper than the equivalent volume ofurethane.

The improved door structure has the further advantage of providing drillresistance by the balls encased in urethane in the areas 14 and 16 whichcover the entire front and outer sides of the door. Thus drillresistance is provided completely over all outer door surfaces that aresubject to drilling attack. In prior doors it has not been possible toprovide drill resistance to such complete extent.

The fundamental concept of the present invention provides a protectivedoor structure in which the door body, which otherwise may be termed itscase or jacket is formed of urethane plastic material, molded toeliminate requirements of machining, etc., for finishing the outersurface, contour, shape and finish, and which may be colored if desiredto eliminate painting; the urethane door body having embedded therein asinternal reinforcement, metal plates, cages, etc., not only to supportlocking components assembled in the door but also to reinforce theurethane door body as well as to resist various modes of attack; and thedoor body also having a series of metal balls embedded within desiredportions or areas ofthe urethane body to increase drill resistance.

Accordingly, the new protective door structure provides an improveddrill-resistant door structure which is very simplified in constructionand manufacture; provides efficient drill resistance to attack by usualand known means used by an intruder attempting to gain illegal forced orsurreptitious entry to a protected area; eliminates costly arrangementheretofore required for doors or safes, vaults and other similarprotective containers; and achieves the objectives described and solvesproblems that have existed in the art.

In the foregoing description, certain terms have been used for brevity,clearness and understanding; but no unnecessary limitations are to beimplied therefrom beyond the requirements of the prior art, because suchterms are used for descriptive purposes and are intended to be broadlyconstrued.

Moreover, the description and illustration of the invention is by way ofexample, and the scope of the invention is not limited to the exactdetails shown or described.

Having now described the features. discoveries and principles of theinvention, the manner in which the improved protective door structuremay be made and used, the characteristics of the new structure, and theadvantageous, new and useful results obtained; the new and usefulstructures, devices, elements, arrangements, parts, and combinations areset forth in the appended claims.

I claim:

1. A safe door including a one-piece integral matrix case of urethaneplastic material having front, rear and edge portions forming theexternal door shape, protective metal plate means embedded in andreinforcing the matrix case, and a locking mechanism recess formed inthe case rear portion surrounded by the case front and edge portions.

2. The door defined in claim 1 in which the door case has a frontsurface, in which the reinforcing plate means includes a plate in thecase front portion spaced from the front surface, and in which a seriesof drill resistant balls substantially contacting each other is embeddedin the entire case front portion between said plate and front surface.

3. The door defined in claim 1 in which a series of drill-resistantballs substantially contacting each other is embedded in plastic matrixmaterial throughout the case.

4. The door defined in claim 1 in which the door case has a frontsurface, in which the plate means includes a plate having a surfacespaced from but parallel with the front surface, and in which a seriesof drill-resistant balls substantially contacting each other is embeddedin the plastic matrix case between the door front surface and thelocking mechanism recess.

5. The door defined in claim 4 in which the balls are embedded in thematrix case on both sides of the plate.

6. A safe door including a matrix case of urethane plastic materialhaving front, rear and edge portions and an edge surface forming theexternal door shape, protective metal plate means embedded in andreinforcing the matrix case, the reinforcing plate means including aringlike member in the case edge portion spaced from the edge surface, aseries of drill-resistant balls embedded in the case edge portionbetween said ringlike member and edge surface, and a locking mechanismrecess formed in the case rear portion surrounded by the case front andedge portions.

7. A safe door including a matrix case of urethane plastic materialhaving front, rear and edge portions and front and edge surfaces formingthe external door shape, protective metal plate means embedded in andreinforcing the matrix case, the reinforcing plate means including aplate in the case front portion spaced from the front surface and aringlike member connected with the plate in the case edge portion spacedfrom the edge surface, a series of drill-resistant balls embedded in thecase front portion between the plate and front surface and in the caseedge portion between the ringlike member and edge surface, and a lockingmechanism recess formed in the case rear portion surrounded by the casefront and edge portions and the ringlike member.

8. The door defined in claim 7 in which the drill resistant balls aremetal balls selected from the class consisting of spherical balls andshot.

9. The door defined in claim 7 in which the case, plate and ringlikemember are circular in shape.

10. The door defined in claim 7 in which additional protective platesare embedded in the matrix connected to the first named plate andsurrounded by the ringlike member.

11. A safe door including a matrix case of urethane plastic materialhaving front, rear and edge portions forming the external door shape,protective metal plate means embedded in and reinforcing the matrixcase, the reinforcing plate means including a pair of plates and spacersupport members connected to the plates and holding the plates in spacedrelation in the matrix case, anda locking mechanism recess formed in thecase rear portion surrounded by the case front and edge portions.

12. The door defined in claim 11 in which the door case has an edgesurface, in which the reinforcing plate means includes a ringlike memberin the case edge portion spaced from the edge surface, and in which aseries of drill-resistant balls is embedded in the case edge portionbetween said ringlike member and edge surface.

13. A safe door including a matrix case of urethane plastic materialhaving front, rear and edge portions and an edge surface forming theexternal door shape, protective metal plate means embedded in andreinforcing the matrix case, a locking mechanism recess formed in thecase rear portion surrounded by the case front and edge portions, aseries of drill-resistant balls embedded in the ease adjacent the edgesurface, lock bolt openings formed in the case and plate means extendingfrom the locking mechanism recess to said edge surface, and the embeddedballs deterring drilling from the exterior of the door toward said lockbolt openings.

14. A safe door including a matrix case of urethane plastic materialhaving front, rear and edge portions, an edge surface and a frontsurface forming the external door shape, a protective metal plateembedded in and reinforcing the matrix case having a surface spaced frombut parallel with the front surface of the door, a locking mechanismrecess formed in the case rear portion surrounded by the case front andedge portions, a series of drill-resistant balls substantiallycontacting each other embedded in the entire plastic matrix case betweenthe door front surface and the locking mechanism recess and adjacent theedge surface, lock bolt openings formed in the case extending from thelocking mechanism recess to said edge surface, and the embedded ballsdeterring drilling from the exterior of the door toward said lock boltopenings.

1. A safe door including a one-piece integral matrix case of urethaneplastic material having front, rear and edge portions forming theexternal door shape, protective metal plate means embedded in andreinforcing the matrix case, and a locking mechanism recess formed inthe case rear portion surrounded by the case front and edge portions. 2.The door defined in claim 1 in which the door case has a front surface,in which the reinforcing plate means includes a plate in the case frontportion spaced from the front surface, and in which a series of drillresistant balls substantially contacting each other is embedded in theentire case front portion between said plate and front surface.
 3. Thedoor defined in claim 1 in which a series of drill-resistant ballssubstantially contacting each other is embedded in plastic matrixmaterial throughout the case.
 4. The door defined in claim 1 in whichthe door case has a front surface, in which the plate means includes aplate having a surface spaced from but parallel with the front surface,and in which a series of drill-resistant balls substantially contactingeach other is embedded in the plastic matrix case between the door frontsurface and the locking mechanism recess.
 5. The door defined in claim 4in which the balls are embedded in the matrix case on both sides of theplate.
 6. A safe door including a matrix case of urethane plasticmaterial having front, rear and edge portions and an edge surfaceforming the external door shape, protective metal plate means embeddedin and reinforcing the matrix case, the reinforcing plate meansincluding a ringlike member in the case edge portion spaced from theedge surface, a series of drill-resistant balls embedded in the caseedge portion between said ringlike member and edge surface, and alocking mechanism recess formed in the case rear portion surrounded bythe case front and edge portions.
 7. A safe door including a matrix caseof urethane plastic material having front, rear and edge portions andfront and edge surfaces forming the external door shape, protectivemetal plate means embedded in and reinforcing the matrix case, thereinforcing plate means including a plate in the case front portionspaced from the front surface and a ringlike member connected with theplate in the case edge portion spaced from the edge surface, a series ofdrill-resistant balls embedded in the case front portion between theplate and front surface and in the case edge portion between theriNglike member and edge surface, and a locking mechanism recess formedin the case rear portion surrounded by the case front and edge portionsand the ringlike member.
 8. The door defined in claim 7 in which thedrill resistant balls are metal balls selected from the class consistingof spherical balls and shot.
 9. The door defined in claim 7 in which thecase, plate and ringlike member are circular in shape.
 10. The doordefined in claim 7 in which additional protective plates are embedded inthe matrix connected to the first named plate and surrounded by theringlike member.
 11. A safe door including a matrix case of urethaneplastic material having front, rear and edge portions forming theexternal door shape, protective metal plate means embedded in andreinforcing the matrix case, the reinforcing plate means including apair of plates and spacer support members connected to the plates andholding the plates in spaced relation in the matrix case, and a lockingmechanism recess formed in the case rear portion surrounded by the casefront and edge portions.
 12. The door defined in claim 11 in which thedoor case has an edge surface, in which the reinforcing plate meansincludes a ringlike member in the case edge portion spaced from the edgesurface, and in which a series of drill-resistant balls is embedded inthe case edge portion between said ringlike member and edge surface. 13.A safe door including a matrix case of urethane plastic material havingfront, rear and edge portions and an edge surface forming the externaldoor shape, protective metal plate means embedded in and reinforcing thematrix case, a locking mechanism recess formed in the case rear portionsurrounded by the case front and edge portions, a series ofdrill-resistant balls embedded in the case adjacent the edge surface,lock bolt openings formed in the case and plate means extending from thelocking mechanism recess to said edge surface, and the embedded ballsdeterring drilling from the exterior of the door toward said lock boltopenings.
 14. A safe door including a matrix case of urethane plasticmaterial having front, rear and edge portions, an edge surface and afront surface forming the external door shape, a protective metal plateembedded in and reinforcing the matrix case having a surface spaced frombut parallel with the front surface of the door, a locking mechanismrecess formed in the case rear portion surrounded by the case front andedge portions, a series of drill-resistant balls substantiallycontacting each other embedded in the entire plastic matrix case betweenthe door front surface and the locking mechanism recess and adjacent theedge surface, lock bolt openings formed in the case extending from thelocking mechanism recess to said edge surface, and the embedded ballsdeterring drilling from the exterior of the door toward said lock boltopenings.